Paper pulp screening machine



May 15, 1934. N. M. KNIGHT 1,959,210

PAPER PULP SCREENING MACHINE Filed Dec. 2S, 1931 2 Sheets-Sheet l 1:. DLE- -y l J6 V/s- 11 a I ,ZZ\ /19 f l O O d I O O 6.

if" ,f l@ 10 f//f @ZZ/07177@ MaylS, 1934. N M, KNlGHT l 1,959,210

PAPER PULP SCREENING MACHINE Filed Dec. 2s, 1931 2 shams-sheet 2 Patented May 15, 1934 STATES ATENT OFFICE Claims.

My present invention relates to pulp screens and more particularly to a wood pulp screening machine. y

Pulp screening machines as used in pulp mills 5 are used for screening out foreign matter such as dirt particles and other matter not desired in the pulp fibers.

Pulp screening machines in general, as well as in the present invention are designed to operate upon the wood pulp when such pulp is in a fluid condition and saturated with a surplus of water and other ingredients. In such a condition the pulp contains more or less objectionable matter which `must be separated from the clean fibers. The pulp is ordinarily of a lighter specific gravity that the objectionable matter and when properly agitated may be separated, the sediment comprising the dirty particles falling to the lowest level while the lighter fibrous particles are thrown oif and pass on to further manipulation prior to becoming paper.

The principal object, therefore, is an improved wood pulp screening machine;

Another object is to produce a screening machine with few moving parts with the object of having long life; another object is a screening machine so designed that the screening plates proper will have long life;

Another object is a screening machine which will give great production as to capacity, and

Still another object is to produce a screening machine which will give the increased capacity above referred to at a reduced horse power consumption over present methods of pulp screening;

Other objects and novel features comprising the construction and operation of my invention will appear as the description of the same progresses. l

In the drawings illustrating the preferred embodiment of my invention:

Fig. 1 illustrates a side elevation as viewed from the discharge side;

Fig. 2 is an end elevation as viewed from the driving end;

Fig. 3 is a vertical cross-section taken on the line 2-2 of Fig. 2;

Fig. 4. is a transverse vertical cross-section taken on the line 4wd of Fig. 3;

Fig. 5 is a view of the drive mechanism shown in the extreme right end of Fig. 3, the scale having been enlarged to more clearly show the speciiic construction, and

Fig. 6 shows a transverse cross-section taken lon the line 6-6 of Fig. 3 showing the cam and cam shaft in elevation.

Referring more in detail vto the drawings, 10 indicates the base of themachine at either end of which is mounted casings 11 and 12. Connecte ing the casings 11 and 12 at their upper portions is a flanged housing member 13 the central portion of which is provided with a pulp inlet port le communicating with the interior of the machine. In the base 10 of the machine is located an outlet l5 through which the rejected matter passes after having been screened from the pulp. It will be noted in Fig. 3 that the discharge opening 15 is centrally located with respect to the horizontal axis of theY machine and further provided with sloping bottom portions 16 comprising a portion of the base of the machine for the purpose of facilitating the flow of rejected matter to the ports 15, Surrounding the inner flanges 17 and 18 of the casings 11 and l2 respectively is a perforated screen 19 through which the wood pulp is passed. The screen 19 is preferably made in two half portions as shown inFiggl and supported at the top and bottom by means of a pair of horizontally disposed angle members 20 and 21 respectively the ends of which extend beyond the end of the screen and land on the flange 17 of the casing 11 and the flange 18 of the opposite end casing 12. The angles 20 and 21 may be solidly fixed to the screen portions 19 at their bottom sides and bolted together at 22 their vertical sides. In most cases where the construction is like that shown in Fig. 3, I prefer to carry the edges of the screen 19 all the way out to the full end of the angles 20 and 21 such that the screen edge passes over the iianges 17 and 18 thereby preventing any pulp from passing into the casings 1l and 12 without first passing the screen.

Horizontally disposed Within the casings l1 and 12 are housings 23 and 24 with their respective bushings 25 and 26 within which is journalled a solid shaft member 27 and hollow shaft member 28. The housing member 24 extends outward in a horizontal direction and forms a casing around the drive mechanism, better shown in Fig. 5. A drive shaft 29 mounted in one side of the housing 24 at right angles thereto is provided with a double acting cam 30 adapted to operate in a counter clockwise direction and engaging with cam rollers 31 and 32. The roller 31 is pivoted in the end of the reduced portion of the shaft 27, as indicated at 27a. The roller 32 is mounted in an extension portion 33 of the hollow shaft 28. As viewed in Fig. 3, when the Pico cam revolves in a counter clockwise direction the rollers 3l and 32 are oscillated in a horizontal direction imparting a similar motion to the shaft members 2'7 and 28. Centrally located within the screen 19 are a pair of oppositely opposed cones and 36, the cone 35 is secured in a xed position to the shaft 27 by means of set screw 37 passing through the cone hub 38, and the other cone 36 being similarly attached to the hollow shaft 28-'through its hub 39 by means of the set screw 40.

In operation, when the cam 30 causes the shaft 27 and shaft 28 to oscillate, the pulp deposited on the screen 19 is drawn through the screen and passed up over the cone sides 41 into the .chambers 42 and 43 and thence out through `the delivery ports 44 and 45.

In order to facilitate the oscillation` of the cone members 35 and 36 and to make their movement more positive, I have provided'compression springs 46 and 47around the shafts 2'7 and 28 between the hubs 38 and 39'respectively of the cones 35 andY 36 and their respective end casings such that Vthe shafts 27 and 28 will return together with the rolls V3l and 32 and always keep contact with the periphery of the cam 30. Around the springs 46 and 47 I have placed a water-tight guard member 50 adapted` to be clamped tightly over the ends of the housings 23 and 24 and their adjacent cone hubs 38 and 39. Thisguard member 50 is composed of any suitable material, as rubber, which will allow for the end motion of the cones 35 and 36.

Throughout the-design vof my invention as disclosed in the-drawings all parts are interchangeable and symmetrical thereby vreducing vibration to a minimum, and although I have shown the preferred embodiment of my invention somewhat in detail it is tobe understoodthat I am entitled to alter the proportions and design within wide limits without departing from thefspirit of the invention.

Having thus described my invention what I claim as new, is:

l. A pulp screening machine, comprising a housing, a screen located within said housing, a opening in said housing adapted to admit pulp to said screen, pulp outlet chambers located at eitherlend of said screen, a waste' outlet located in said housing below said screen, oscillating members horizontally disposed within said screen adapted to pass said pulp from the inside of said screen to said pulp outlet chambers, oscillating shaft and sleeve member attached to said oscillating membersand means `for oscillating said shaft and sleeve members.

2. A pulp screening machine comprising a housing, a screen locatedv within said housing, an opening in said housing adapted to admit pulp to thefsaid screen, a waste outlet located in vsaid housing below said screen, oscillating members horizontally disposed within said `screen adapted to pass said pulp from the inside of said screen to pulp outlet chambers located at either side of said housing, a shaft and sleeve member associated with said oscillating members, a cam member and cam rolls associated with said shaft and sleeve members adapted to oscillate said latter members.

3. A pulp screening machine comprising a housing, a screen located within said housing, anl opening in said housing adapted to admit pulp to the said screen, a depressed waste outlet rlocated in said housing below said screen, conical oscillating members horizontally disposed within said screen adapted to pass said pulp from the inside of said screen to a pulp outlet chamber located at either end of said housing, a shaft and sleeve member associated with said oscillating members, a double acting cam and cam rolls located at either side thereof associated with `the said shaft and sleeve members adapted tov oscillate said members.

4. A pulp screening' mach-ine comprising a housing, a screen located Within said housing, an opening in said housing adapted to admit pulp to the said screen, Va depressed waste outlet lo- -l cated in said housing below said screen, conically shaped oscillating members horizontally disposed within said screen adapted to pass said pulp from the inside of said screen to a pulp outlet chamber located at either end of the said housing, a shaft and sleeve member slidably and horizontally disposed through the end walls of the said housing, said shaft having a reduced end portion extending into said sleeve member, an exterior housing member located about the extremities of said sleeve and shaft members, a drive shaft mounted through the said exterior housing at right angles to it, a double acting cam mounted at the end of said drive shaft, a

hollow box member located within said exterior housing member solidly Xed to the extremity of said sleeve-member and adapted to surround said drive shaft member, a cam roll rotatably mounted in said hollow box member adjacent one ofthe faces of the said cam, a second cam roll rotatably mounted in the extremity of the reduced vportion of the oscillating shaft adjacent the other of the faces `of the said double acting cam.

`5. A pulp screening machine comprising a housing, a screen located within said housing,

an opening in said housing adapted to admit pulp .to the said screen, a depressed waste outlet located in said housing below said screen, oscillating members horizontally disposed within lsaid screen adapted to pass said pulp from the inside of said screen to a pulp outlet chamber located at either end of said housing, compressibly maintained shaft and sleeve members associated with said oscillating members.

NELSON M. KNIGHT.

lll() 

